Correlated Color Temperature Estimation Using Digitally Controlled Spectroscopic Device

AS7341 is a multispectral digital sensor used as a spectrometer embedded on a breakout board. It measures the spectral response via eight visible spectrum channels ranging from 350nm to 750nm and two additional channels for clear light and NIR measurement. The device employs an Inter-Integrated Circuit interface for process control and access to data. It was assembled with an open-source microcontroller board to estimate the correlated color temperature of standard display monitors. The device was calibrated using an industrial standard X-Rite color checker chart by measuring the chromaticity coordinates. Upon successful calibration, a few display monitors were analyzed under similar device settings for comparative study. The Correlated Color Temperature (CCT) values obtained using the device from the display screen of Apple's MacBook Air M2 (2022) were found to be the closest resemblance to the predicted values. Further, the CCT range for all devices correlated with the expected CCT range provided by different manufacturers. This experimental design demonstrated that the device can be used for CCT estimation and obtain inferences regarding the intensity and age of various light sources. The small size and portability of the device add to the functionality of the device as an effective spectrometer.